This study represents the second phase of a long-term study begun in 1993. In the first phase, animals did not show long-term immunological or hormonal deficits, but did show behavioral adjustments to an unstable social environment. This study was repeated with an additional 16 juvenile rhesus monkeys. For this study, a short-term environmental disturbance was introduced 3 times prior to scheduled bleeding for physiological samples (3 of 9 bleeding samples). Sampling was completed in October, 1996, and assays for catecholamines and immune measures were completed in December, 1996. Cortisol and behavioral data are in the process of being analyzed.